There seems to be some confusion about how delivery dates and serial numbers determine when back-ordered items are delivered and how priority is determined for upcoming purchases like the RPP's, and presumably EPIC-X, etc..
While a camera's serial number is a potential indicator of where the owner's place in line may fall, the real important piece of information is when that camera was originally shipped or delivered from RED. Delivery dates are the key factor as that keeps someone with a low serial number from jumping to the front of the line if they happened to not actually buy their camera until much later in RED's delivery cycle.
The original delivery date and serial number of a camera will transfer to any new owner of that camera.
Those buying used RED ONEs, especially cameras with a lower serial number, should also verify the original delivery date of the camera. The original delivery date will do far more to determine the priority associated with that camera than its serial number.